It kinda depends on how much you can afford to pay the proffesionals....(i know...as little as possible..)
Sanding all the paint off is a good start... removing as much trim helps keep costs down...
Please dont take this the wrong way...but if you want a quality paint job then leave the rest to the proffesionals... where i work (painting cars / bikes) people say they want something painted, but it will be totally prepared for paint...well when we get it, its often more work rectifying problems than if they hadn't touched it in the first place...! By far the majority of time and hard work in a top quality paint job is in the prep...
Having said that, the last rippley fibberglass car i repaired / painted was an old TVR (my own..) and once repaired, i sanded the whole car with a block/ by hand, with 80 grit (yes, 80 grit..) ripped off most of the paint, and all the high spots, then high build primed everything, sanded it again with something like 240 grit, primed it again, sanded again with 600, then painted it, then clearcoated it....then sanded it again with 2000 grit, then machine polished it....mirror finish and pin straight....
If you want to do as much as possible, sand everything, and high build prime it, then give it to the paint shop to final sand / prep...
(if you use 2 pack products, PLEASE use proper breathing apparatus, its deadly stuff....)
I hope i havn't put you off, i greatly admire your enthusiasm, dont go too mad with that sander on a curvy car, the best jobs are done by hand...with blisters, blood, sweat and tears.....
